FEVERS. 503 



concoct it, so as to render it either altogether innocent, or, at 

 least, fit for being more easily thrown out of the body. This 

 doctrine, however, although of as great antiquity as any of the 

 records of physic now remaining, and although it has been re- 

 ceived by almost every school of medicine, yet appears to me to 

 rest upon a very uncertain foundation. There are fevers pro- 

 duced by cold, fear, and other causes, accompanied with all the 

 essential circumstances of fever, and terminating by sweat, but, 

 at the same time, without any evidence or suspicion of morbific 

 matter. 



There have been fevers suddenly cured by a haemorrhagy, so 

 moderate as could not carry out any considerable portion of a 

 matter diffused over the whole mass of blood ; nor can we 

 conceive how the morbific matter could be collected or deter- 

 mined to pass by such an outlet as in that case is opened. 



Even supposing a morbific matter were present, there is no 

 explanation given in what manner the concoction of it is per- 

 formed ; nor is it shown that any such change does in fact take 

 place. In certain cases indeed it is evident, that a noxious matter 

 is introduced into the body, and proves the cause of fever : but 

 even in these cases, it appears that the noxious matter is thrown 

 out again, without having suffered any change; that the fever 

 often terminates before the matter is expelled; and that upon 

 many occasions, without waiting the supposed time of concoc- 

 tion, the fever can be cured, and that by remedies which do not 

 seem to operate upon the fluids, or to produce any evacuation. 



L. While we thus reason against the notion of fever being an 

 effort of nature for concocting and expelling a morbific matter, 

 I by no means intend to deny that the cause of fever frequently 

 operates upon the fluids, and particularly produces a putrescent 

 state of them. I acknowledge that this is frequently the case ; 

 but, at the same time, I maintain, that such a change of the 

 fluids is not commonly the cause of fever ; that very often it 

 is an effect only ; and that there is no reason to believe the ter- 

 mination of the fever to depend upon the expulsion of the pu- 

 trid matter. 



LI. Another opinion which has prevailed remains still to be 

 mentioned. In intermittent fevers, a great quantity of bile is 

 commonly thrown out by vomiting ; and this is so frequently 



